/*
 * Copyright 2009 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.testgal.client.impl.util;

import com.google.gwt.user.client.ui.SimplePanel;
import com.google.gwt.user.client.ui.Widget;

/**
 * Yet another LazyPanel. This is here just to avoid dependencies beyond GWT 1.5.
 *
 * @author Brian Slesinsky
 */
public abstract class LazyPanel extends SimplePanel {

  protected abstract Widget createWidget();

  public void enableWidget() {
    if (getWidget() == null) {
      setWidget(createWidget());
    }
  }

  @Override
  public void setVisible(boolean visible) {
    if (visible) {
      enableWidget();
    }
    super.setVisible(visible);
  }

}
